Marine boiler



April v8, .1930. o, HARTMANN ET AL MARINE BOILER Original Filed June 22, 1927 2 Sheets-Sheet l /n venzor: OTTO H. HARTMAHN I HEINRICH PEPER RN a Ahorney April 1930- o. H. HARTMANN ET AL 1,754,167

MARINE BOILER Original Filed June .22, 1927 2 Sheets-Sheet 2 OTTO H. HART/WANN- HEINRICH PEPERKORN Patented Apr. &, 1930 @EFMCE OTTO H. HARTMANN AND HEINRICH PEE'ERKORH, 0F KAfiSEL-WILHELMfiI-IOHE, GER- MANY, ASSIGNORS '10 SCHMIDT$CHE HEISSIJAhEPF-G. M. B. 3., OF KASSEIJWIIJ- H ELIMISI-IOHE, GERMANY, A COREORATIOIN OF QERIVIANY MARINE BOILER Application filed, June 22, 1927, Serial No. 200,635, and in Germany'June 26,. 1926. Renewed February 25, 1930.

Uur invention. relates to an arrangement for generating high-pressure steam in marine boilers of the return flue type, in which the boiler is divided into two steam generators of different pressure. In marine boilers there is difficulty in providing sufficient space for the requisite heating surface for the additional high-pressure boiler, owing to the limited space available, and it is highly desirable not to have to depart from the return flue type of marine boiler which has been found to be particularly satisfactory, the so-called wagon boiler,in the transition to the high-pressure steam system. a Our present invention shows how thismay be done in a satisfactory manner. Special attention is paid to the peculiarities of marine practice, the difliculties due to the kind of feed water used and 01": ensuring safety from explosion being specially kept in view.

According to the present invention the lowpressure boiler ofthe steam generating plant is formed by the fire tube boiler which is heated by the returning heating gases and in the. construction and general arrangement of which as compared with the constructional forms hitherto used nothing is changed, while the high-pressure steam generator is an indirectly heated boiler, the heat-absorbing part of which is located in the fire box of the low-pressure boiler.

According to our invention the greater part of the heat-absorbing part of the heating elements of the indirectly heated high-pressure boiler is located (when viewed in the direction of fiow of the heating gases) in front of the reversing chamber of the boiler, while a part of the heating elements is located in the said reversing chamber. That part 01": the heat-absorbing water tubes of the indirect heating system of the high-pressure steam generator lying in front of the reversing chamber may be positioned either in a fire box below the low-pressure fire tube boiler in place of the flues otherwise located in this place or this part of the water tubes may be positioned in a fire box placed in front of the fines. In the reversing chamber besides the second part of theheat-absorbing water tubes of the indirect heating system of the highpressure steam generator there are also superheaters for the high-pressure and for the low-pressure steam. Preferably the supporting members for the supporting bands of the low-pressure fire tube boiler are made hollow, so that the combustion air can flow through them on its way from the air heater to the fire.

In the accompanying drawings different constructional forms of the invention are shown by way of example.

Figure 1 is a longitudinal section through a marine boiler according to the present in vention, having the fire box belou the fire tube boiler and in the fire box a portion of the heat absorbing water tubes oithe heating system of the high-pressure steam generator.

Figure 2 isa i' ront view of this boiler, and

Figure 3 a view from above.

Figure lis a diagrammatic view of two boilers of the kind shown in Figures 1 to 8 arranged side by side.

Figure a longitudinal section through a modified constructional form of the boiler.

The boiler shown in Figures 1 to 3 consists as to its low-pressure part of a drum 1 of the usual kind, through which fire tubes 2 ex tend. The heating tubes 2 open into an uptake 3 which leads into the smoke stack 4.

Above the uptake 3 a heater 5 for the com- -may be provided in the usual manner, which are connected to headers 7. The drum 1 rests on supporting bands 8 which are hinged at either side by pins 9 to supporting members 10 resting on the foundation. These supporting members are hollow. At the top they are connected by pipes 11 to the air heater 5 and at the bottom to the space below the grate 12. The supporting members 10 thus also act as pipes for the heated combustion air. The hinged suspension of the supporting band 8 provides a certain amount of give to allow for expansion due to heat and the like. The drum 1 rests on these supporting bands. For the rest it is supported with respect to the supporting member by abutments 1.3 which are, however, not attached to the drum.

The high-pressure part of the boiler is provided with indirect heating. A drum 14 is used for generating the working steam, which is supported by brackets 15 or the like on the stoke-hole bulkhead. In the water space of the drum 14 are heating coils 16 which form the heat-emitting part of the indirect heating system. The heat-absorbing part of this heat ing system is formed by tubes 17 and 17 The tubes 17 lie in a the box formed below the fire tube boiler 1 and are preferably so positioned as shown in Figure 2, that they form a wall 18 in the middle of the fire box, by which the fire box is divided longitudinally into two parts. The tubes 17 also form the side walls and the front wall of the fire box. At the bottom they are connected to water drums 19 and at the top to water and steam drums 20 which act as equalizing drums in a known manner. From the drums 20 pipes 21 lead to the heating coils 16, from whichthe condensate is led away'through pipes 22 to the drums 19. r p

The heat-receiving tubes 17 lying in the reversing chamber 23 are arranged in several superposed coils, so that they form a heat protection for the tubes of a high-pressure superheater 24 which is also located in the reversing chamber. Besides this high-pressure superheater 24 a low-pressure superheater 25 is also provided in the reversing chamber, which alone or incombination with the superheater tubes 6 servesfor superheating the low pressure steam of the boiler 2. Preferably the upper part 26 of the rear wall of the reversing chamber 23 is formed by superheater tubes of the high-pressure superheatert24, the lower part 27 of the reversing chamber 23 being formed by additional water tubes of the heat-absorbing part of the indirect heating system. of the high-pressure steam generator. A fire-resisting wall 28 may be provided in the usual manner. A low-pressure feed pump 29 feeds the lowpressure boiler 1 with feed water which is taken from a tank 30. Ahigh-pressure feed pump 31 withdraws heated water from the low-pressure boiler and delivers it to the high-pressure drum 14 through a pipe 33.

The high-pressure drum 14 instead of resting on a bracket fixed to the stoke-hole bulkhead maybe supported on pillars or the like.

In Figure 4 an arrangement of twomarine boilers of the kind described with reference to Figures 1 to 3 placed side by side is shown diagrammatically the two uptakes are in this arrangement united in the usual manner to form a common smoke stack 4. Each of the two boilers lying side by side is for the rest constructed exactly like the boiler of Figures 1 to 3.

' Vhile the construction described above is intended and suitable more particularly for boilers which are originally designed as highpressure boilers, the constructional form shown in Figure 5 is intended more particularly for the conversion of existing marine boilers into high-pressure boilers. The fire tube boiler 1, which in this case as well is still used as low-pressure boiler, together with the flues 34 extending through it remains substantially unaltered, the only difference being that the reversing chamber and the rear wall 35 are somewhat modified. This arrangement, like the previous example, also comprises the fire tubes 2, the uptake 3, the smoke stack 4, the air heater 5 and may comprise the superheater tubes 6 lying in the fire tubes and the collecting chambers 7. In this arrangement the grate 12 however lies in front of the fiues, in front of which there is a separate fire box. This fire box is again bounded by or contains the heat-absorbing tubes 17 of the indirect heating system of the high-pressure steam generator. This system again contains the drum 14, the heating elements 16, the lower collectors 19, intermediate drums 20, pipes 21 for supplying the heating steam and pipes 22 for leading away the condensate. One portion of the heat-absorbing tubes 17 is again locatedin the reversing chamber 23, these tubes forming the entire rear wall 27 a of the reversing chamber. A fire-resisting wall 28 is again provided. The tubes 27 open at the bottom in drums 19' which are connected to the drums 19 by a pipe 39 Atthe top the tubes 27 are connected to drums 19 which convey the heating steam through a pipe 21 which is connected to the pipe 21 to the heating elements 16. In the reversing chamber 23 there is also provided the highpressure superheater 24 and the low-pressure superheater 25. The low pressure feed pump 29 again conveys feed water from a tank 30 to the low-pressure boiler 1 while the high-pressure pump31 draws water through thepipe .32 from the low-pressure boiler and conveys it through a pipe 33 to the high-pressure drum 14. In the example shown in Figure 5 this high-pressure drum 14 rests in a support- The constructional examples of a marine boiler of the return flue type show that it is possible without enlarging the areacovered by the usual types of boilers and space occupied by them to make the marine boiler suitable for the generation of high-pressure steam. In the high-pressure drum 14, for instance, steam of 60 atmospheres may be generated, while in the low-pressure boiler l steam of 12'to 15 atmospheres is generated. The high-pressure steam may be conveyed to the high-pressure stage of the prime mover for performing work, while the low-pressure steam from the low-pressure boiler is conveyed to the low-pressurestages after mixing with the exhaust steam from the highpressure In this way it is possible to construct new marine boiler plants and adapt existing plants in such a manner that the ad vantages of the higlrpressure steam are mad available for the propulsion of ships. Through the use of indirect heating in the highpressure steam generator the high-pressure steam maybe generated without any danof explosion. This safety from explosion may be further increased by sub-dividing in a known manner the indirect heating system in which the heat carrier continuously circulates, so that there are a plurality of independent circulating systems of the heat carrier.

Having now particularly described and a.- certained the nature of our said invention and in what manner the same is to be performed, we declare that what we claim is 1. In a marine boiler of the return flue type which is subdivided into two steam genei" ators 0t difierent pressure, in combination a fire box, a reversing chamber in communication with the fire box, a fire tube boiler serving as the low-pressure steam generator, said fire tube boiler being in communication with the exit end of said chamber and thereby heated by the gases after their change in direction, and an indirect-l7, heated high-pressure steam generator having heating elements with heat absorbing parts, the greater portion of said heat absorbing parts being located within the fire box and another portion thereof being located within the reversing chamber.

2. A marine boiler oi the return flue type which is subdivided into two steam genera,

tors of different pressure, having in combination a fire box, a reversing chamber in communication with the fire box, fire tube boiler serving as a low-pressure steam generator and communicating with the exit end of said reversing chamber, said fire tube boiler being heated by the return flow heating gases, and an indirectly heated high pressure steam generator, the said fire box being provided in place of fines below the fire tube boiler and the said high-pressure steam generator having heating elements with heatabsorbing parts formed by water tubes lying in part in the said fire box and in part in the reversing chamber.

3. In a marine boiler adapted to generate both high and low pressure steam, a fire box, an uptake to a stack, a reversing chamber in communication with the fire box a low pressure fire tube boiler having its tunes substantially elevated with respectto the fire box and connected between said reversing chamber and the uptake to the stack, and hi h pressure steam generator, the heat receiving elements 01": which re disposed within the fire box and within said reversing chambe 4:. A marine boiler of the return flue type which subdivided into two steam generators of different pressure, having in combinareversing chamber, said fire tube boiler be-- ing heated by the return iiow heating gases, and an indirectly heated higlrpressrre stez 1 generator having heating elements with heat absorbing parts formed by water tubes located in part in the fire box and in part in the reversing chamber, a number of the said. water tubes lying at the rear wall of the reversing chamber.

5 A marine boiler oit' thereturn flue type which is made up of two steam generators of different pressures, having in combination a fire box, a grate, a combustion gas channel connected to the fire box, a fire tube boiler having its tubes in communication with said channel and serving as thelow-pressure steam generator, a high-pressure steam generator having its heat absorbing parts lying in part in the fire box and in part in the channel, an air heater, hollow upright stanchions alongside the low-pressure fire tube boiler, and supporting bands upon which the fire tube boiler rests in suspension, the ends of said bands being pivotally connected to the upright stanchions, at least one of said stanchions communicating at one end with the air heater and at the other end with the space under the grate.

6. A marine boiler of the return flue type, which is subdivided into two steam generators of dilierent pressure, having in combination a fire box, a reversing chamber, a fire tube boiler heated by the return flow heating gases serving as the low-pressure steam generator, and an indirectly heated high-pressure steam generator, the said fire box being provided in place of fines below the fire tube boiler, the said high-pressure steam generator having heating elements with heat-absorbing parts formed by water tubes lying in part in the said fire box and in part in the reversing chamber, and a superheater for the high-pressure steam and a superheater for the lowpressure steam, these superheaters being situated in the reversing chamber.

7. In a marine boiler of the return line type which is subdivided into two steam generators of difierent pressure, in combination a fire box, a reversing chamber in communica tion with the fire box, a fire tube boiler serving as the low-pressure steam generator said fire tube boiler being in communication with the exit end of said chamber and thereby heated by the gases after their change in direction, an indirectly heated high-pressure steam generator having heating elements with heat absorbing parts disposed Within the fire box and within the reversing chamber, a superheater for the high-pressure steam and a superheater for the low-pressure steam,

these superheaters being located in the reversing chamber.

8. In a marine boiler of the return flue type which is subdivided into two steam generators of differentpressure, in combination a fire box, a reversing chamber in communication with the fire box, a fire tube boiler serving as the low-pressure steam generator said fire tube boiler being in communication with the exit end of said chamber and thereby heated by the gases after their change in direction, an indirectly heated high-pressure steam generator having heating elements with heat absorbing parts disposed within the fire box and within the reversing chamber, a V

superheater for the high-pressure steam and a superheater for the low-pressure steam, the first mentioned superheater being located in front of the fire tube boiler.

In testimony whereof we have aflixed our signatures.

OTTO H. HARTMANN. HEINRICH PEPERKORN. 

